.hack SIGN (2002)

The series follows the story about Tsukasa being mind-trapped into the game. Despite being a "fantasy quest type adventure", it does not rely on action sequences. Instead, the show is driven by mystery, slowly revealing its secrets to the viewer while paying much attention to the individual characters. Questions like what happened to Tsukasa in the real world, who he really is, and why he cannot log out are driving points of the story.